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Updated: May 15, 2026
07:54
Fluorescence Recovery after Merging a Droplet to Measure the Two-dimensional Diffusion of a Phospholipid Monolayer
Published on: October 15, 2015
Competition for space between a protein and lipid monolayers.
Giovanna Fragneto1, Stéphane Alexandre, Jean-Marc Valleton
1Institut Curie, Labo PSI, 11 rue Pierre et Marie Curie, 75231 Paris, France. fragneto@ill.eu
Colloids and Surfaces. B, Biointerfaces
|December 25, 2012
Summary
Enzyme glucose oxidase (GOx) competes for surface adsorption with fatty acids, inserting into and deforming lipid monolayers. This protein crystallization disrupts membrane structure, forming 3D structures even under compression.
Area of Science:
- Biophysics
- Surface Chemistry
- Biochemistry
Background:
- Competitive adsorption influences surface composition in biological and polymer systems.
- Understanding protein-lipid interactions is crucial for cell membrane dynamics.
Purpose of the Study:
- To investigate the competitive adsorption between glucose oxidase (GOx) and pentadecanoic acid (PDA) at the air/water interface.
- To elucidate the effects of GOx insertion on Langmuir film structure and stability.
Main Methods:
- Fluovideo microscopy was employed to observe adsorption dynamics.
- Langmuir films of pentadecanoic acid were studied in the presence of glucose oxidase.
Main Results:
- Glucose oxidase inserts into PDA monolayers, causing film contraction and domain formation.
- GOx crystallization deforms and destroys domain structures, particularly on heterogeneous surfaces.
- Protein remains at the interface under compression, forming three-dimensional structures.
Conclusions:
- Enzyme adsorption dynamics significantly alter lipid monolayer organization.
- Protein-lipid interfacial interactions can lead to structural changes and self-assembly.
- The study provides insights into protein incorporation and membrane remodeling.
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